[PATCH 9/9] drm: sti: fix delay in VTG programming

Benjamin Gaignard benjamin.gaignard at linaro.org
Fri Dec 5 00:35:07 PST 2014


The HDMI path introduce a delay of 6 pixels.
This delay should be take into account while programming
VTG for the HDMI. Without this delay, the HDMI active
window area is shift of 6 pixel on the right.

Set also timing for DVO output.

Signed-off-by: Benjamin Gaignard <benjamin.gaignard at linaro.org>
---
 drivers/gpu/drm/sti/sti_vtg.c | 25 ++++++++++++++++++++++---
 1 file changed, 22 insertions(+), 3 deletions(-)

diff --git a/drivers/gpu/drm/sti/sti_vtg.c b/drivers/gpu/drm/sti/sti_vtg.c
index 740d6e3..ce7c0c9 100644
--- a/drivers/gpu/drm/sti/sti_vtg.c
+++ b/drivers/gpu/drm/sti/sti_vtg.c
@@ -55,6 +55,9 @@
 #define VTG_IRQ_TOP         BIT(1)
 #define VTG_IRQ_MASK        (VTG_IRQ_TOP | VTG_IRQ_BOTTOM)
 
+/* Delay introduced by the HDMI in nb of pixel */
+#define HDMI_DELAY          (6)
+
 /* delay introduced by the Arbitrary Waveform Generator in nb of pixels */
 #define AWG_DELAY_HD        (-9)
 #define AWG_DELAY_ED        (-8)
@@ -133,10 +136,10 @@ static void vtg_set_mode(struct sti_vtg *vtg,
 	writel(tmp, vtg->regs + VTG_VID_TFS);
 	writel(tmp, vtg->regs + VTG_VID_BFS);
 
-	/* prepare VTG set 1 and 2 for HDMI and VTG set 3 for HD DAC */
-	tmp = (mode->hsync_end - mode->hsync_start) << 16;
+	/* prepare VTG set 1 for HDMI */
+	tmp = (mode->hsync_end - mode->hsync_start + HDMI_DELAY) << 16;
+	tmp |= HDMI_DELAY;
 	writel(tmp, vtg->regs + VTG_H_HD_1);
-	writel(tmp, vtg->regs + VTG_H_HD_2);
 
 	tmp = (mode->vsync_end - mode->vsync_start + 1) << 16;
 	tmp |= 1;
@@ -146,6 +149,11 @@ static void vtg_set_mode(struct sti_vtg *vtg,
 	writel(0, vtg->regs + VTG_BOT_V_HD_1);
 
 	/* prepare VTG set 2 for for HD DCS */
+	tmp = (mode->hsync_end - mode->hsync_start) << 16;
+	writel(tmp, vtg->regs + VTG_H_HD_2);
+
+	tmp = (mode->vsync_end - mode->vsync_start + 1) << 16;
+	tmp |= 1;
 	writel(tmp, vtg->regs + VTG_TOP_V_VD_2);
 	writel(tmp, vtg->regs + VTG_BOT_V_VD_2);
 	writel(0, vtg->regs + VTG_TOP_V_HD_2);
@@ -166,6 +174,17 @@ static void vtg_set_mode(struct sti_vtg *vtg,
 	writel(tmp, vtg->regs + VTG_TOP_V_HD_3);
 	writel(tmp, vtg->regs + VTG_BOT_V_HD_3);
 
+	/* Prepare VTG set 4 for DVO */
+	tmp = (mode->hsync_end - mode->hsync_start) << 16;
+	writel(tmp, vtg->regs + VTG_H_HD_4);
+
+	tmp = (mode->vsync_end - mode->vsync_start + 1) << 16;
+	tmp |= 1;
+	writel(tmp, vtg->regs + VTG_TOP_V_VD_4);
+	writel(tmp, vtg->regs + VTG_BOT_V_VD_4);
+	writel(0, vtg->regs + VTG_TOP_V_HD_4);
+	writel(0, vtg->regs + VTG_BOT_V_HD_4);
+
 	/* mode */
 	writel(type, vtg->regs + VTG_MODE);
 }
-- 
1.9.1



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